In financial institutions and various other businesses, there exists a need to protect and secure money, documents, and other valuable items. For this purpose, it is common for such businesses to provide restricted access chambers such as drawers and cabinets. Access to these chambers is frequently restricted and controlled by key operated cabinet-type locks mounted on the front access panels of the drawers or cabinets. In this way, businesses can limit access to drawers and the like to only those designated employees that have a specific key to a specific lock.
For a number of reasons these businesses, at some time, have to change or remove locks, or take other measures to ensure the integrity of restricted access chambers. For example, in the banking industry it is quite common for a bank or its branch locations to employ part-time tellers that work irregular shifts, at various work stations within a branch. In fact, it is common for a number of part-time tellers to work together at one office or branch. Standard operating procedures that banks typically follow usually require that each teller have a personalized lock-operated cash drawer that is exclusively controlled by the teller against entry by others. For this reason, key control to drawers and integrity thereof is critical. Consequently, because part-time employees frequently change work station locations, or because banks sometimes experience employee turnover, banks must take steps to ensure the integrity of the locks.
Moreover, permanent bank employees must sometimes shift location to any one of multiple work stations within a branch or home office. Accordingly, teller-line equipment that includes locked drawers must be flexible to permit regular personnel reassignments among the various cash drawers throughout an office, without sacrificing the integrity and security of the locks. As one might perceive, maintaining the integrity of locks under these circumstances is difficult at best.
More specifically, when keys are duplicated or shared between employees, the integrity of such restricted access chambers is compromised. Accordingly, some measure of key control is usually required. One way to control the circulation of keys is for a bank to provide a key to a specific lock only to the person who is intended to have exclusive control over a predetermined restricted access chamber. In this way, an employee is motivated to preserve the integrity of the chamber by ensuring that duplicate keys are limited and stay within the employee's control. However, this method of key control greatly limits the ability of a business to shift exclusive control of a restricted access chamber from one employee to another while maintaining confidence that duplicate keys do not exist.
Over the years, banks and other financial institutions have addressed the problem of exclusive control in different ways. For example, with cash drawers, some banks solve this problem by installing multiple locks on the access or closure panels thereof. The locks are positioned side by side, one lock for each teller who is to have exclusive control over the drawer. In this way, any one person who controls one of the locks can also individually and exclusively control the cash drawer. However, this solution is inadequate because the number of employees or tellers having their own designated lock in any one drawer is limited to the number of locks that can physically be installed.
A number of other arrangements and inventions have been created to maintain the integrity of locked restricted access chambers. Most are directed to methods of removing an entire lock mechanism or parts thereof so that locked drawers and the like can be rekeyed thereby enabling businesses to maintain exclusive control over such restricted access chambers.
One of the early designs, disclosed in the U.S. Pat. No. 210,807 to Sargent, is directed to a key operated locking mechanism that is mounted in a predetermined recess formed in the face of a drawer. This design, however, is limited. First, the design requires that a portion of the mounting surface be removed to receive the lock, thereby adding to the expense of its installation as well as permanently modifying the mounting surface. Also, because the lock is attached to the drawer surface with screws, changing the entire lock mechanism requires tools and is therefore slow and somewhat cumbersome.
A subsequent design shown in U.S. Pat. No. 3,824,817 to Orr, discloses a lock mechanism having a key receiving "cylinder" portion, a housing that fits into a recess in the mounting surface, and a retainer spring. When repair, replacement, or modification of the lock is required, the lock cylinder portion can be separated and removed from the lock housing. Thus, when a user requires a lock to operate with new or different keys, the cylinder portion of the lock mechanism must be removed and replaced. With this design, however, a special tool is required for such removal or replacement of the cylinder. Because of this, lock repair or modification is somewhat awkward, and depends on the availability of the tool. Further, like Sargent, a portion of the mounting surface must be permanently modified for the positioning of the lock in the drawer.
More recently, U.S. Pat. No. 4,099,397 to Dauenbaugh was issued disclosing a lock mechanism comprising a sleeve having a removable cylinder mechanism contained therein. Installation requires the sleeve to be fitted in a hole provided in a drawer's access panel. A retainer member secures the cylinder mechanism into operating position. Replacement of the cylinder mechanism is accomplished by removing the same from the sleeve. Although special tools are not necessarily required, the mechanism must be broken down into several components when a cylinder is removed. Thus, when the lock is being re-keyed, or repaired, parts could be lost or misplaced. Moreover, the procedure for reassembly is sufficiently complicated that the user must possess a certain level of skill.
Finally, U.S. Pat. No. 4,873,852 was issued to Neyret disclosing a fixation fork for a cylinder lock plug to retain such locks primarily in automobile doors. The Neyret fixation fork operates by exerting a force on the lock mechanism to bias the same against the door of an automobile. Like Orr, however, a special tool is required for fork removal to access the lock mechanism. Also, the procedure for lock removal requires a series of oscillating movements which makes the procedure slow and tedious.
As seen from the above, banks and other institutions are limited in ways currently available to ensure and maintain the integrity of restricted access chambers. The various lock installation arrangements noted above are primarily directed to semi-permanent installation of whole lock assemblies or parts thereof. None suggests or teaches a way to quickly and easily re-key restricted access chambers. Likewise, none suggests or teaches a satisfactory method to enable businesses and employees alike to maintain exclusive control over locked drawers and cabinets when part-time and permanent employees are shifted among work stations. Accordingly, there exists a need for a quick and simple way for banks and other businesses to maintain exclusive control over locked restricted access chambers.